Hangar roof collapse at Dulles.

Great additional photos, note the text says the hangar is a few years old.

Looks like the builder is in for a massive bill ,if they are found to blame

a few more pics here , it looks a mess
http://www.teamspeed.com/forums/aviation/36535-hangar-collapse-dulles-international-airport.html

Initial reports from the scene state that welded joints failed.

The a/c at the back in the above photo is Eastman Kodak’s Bombardier Global Express, N620K.

Aviation week says the hangar was newly built, some of the planes are leaking fuel and those three are not repairable.

However, the photo above doesn’t make it look that bad.
I wonder what their tails look like?

oops!